It is useful for producers to compare the EPDs of potential breeding animals with their breed average. The current EPDs from the most recent genetic evaluations of 26 breeds are presented in this report. Mean EPDs for growth traits are shown in Table 1 (26 breeds), for other production traits in Table 2 (20 breeds), and for carcass and composition traits in Table 3 (21 breeds). Several breeds also have EPDs and indices that are unique to their breed; these EPDs are presented in Table 4.

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Larry A. Kuehn et al.Across-Breed EPD Tables For The Year 2016 Adjusted To
Breed Differences For Birth Year Of 2014http://digitalcommons.unl.edu/hruskareports/380
http://digitalcommons.unl.edu/hruskareports/380Wed, 12 Oct 2016 12:19:22 PDT
Factors to adjust the expected progeny differences (EPD) of each of 18 breeds to the base of Angus EPD are reported in the column labeled 6 of Tables 1-8 for birth weight, weaning weight, yearling weight, maternal milk, marbling score, ribeye area, fat thickness, and carcass weight, respectively. An EPD is adjusted to the Angus base by adding the corresponding acrossbreed adjustment factor in column 6 to the EPD. It is critical that this adjustment be applied only to Spring 2016 EPD. Older or newer EPD may be computed on different bases and, therefore, could produce misleading results. When the base of a breed changes from year to year, its adjustment factor (Column 6) changes in the opposite direction and by about the same amount.

Breed differences change over time as breeds put selection emphasis on different traits and their genetic trends differ accordingly. Therefore, it is necessary to qualify the point in time at which breed differences are represented. Column 5 of Tables 1-8 contains estimates of the differences between the averages of calves from sires of each breed born in year 2014. Any differences (relative to their breed means) in the samples of sires representing those breeds at the U.S. Meat Animal Research Center (USMARC) are adjusted out of these breed difference estimates and the across-breed adjustment factors. The breed difference estimates are reported as progeny differences, e.g., they represent the expected difference in progeny performance of calves sired by average bulls (born in 2014) of two different breeds and out of dams of a third, unrelated breed. In other words, they represent half the differences that would be expected between purebreds of the two breeds.

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L. A. Kuehn et al.Feed Efficiency And The Microbiota Of The Alimentary Tracthttp://digitalcommons.unl.edu/hruskareports/379
http://digitalcommons.unl.edu/hruskareports/379Wed, 12 Oct 2016 12:16:13 PDT
There is considerable variation in the efficiency that cattle convert feed for maintenance and product (body weight gain, milk, and conceptus). Both intake and gain are polygenic traits and to better understand factors that contribute to variation in feed efficiency more defined phenotypes are needed. Several studies have associated differences in the microbiota of the alimentary tract between obese and non-obese rodents (Turnbaugh et al., 2006), obese and nonobese humans (Ley et al., 2006), and energy metabolism in birds (Torok et al., 2008 and Stanley et al., 2013). These finding suggest that there is a potential relationship between the microbiota of the alimentary tract and feed efficiency in beef cattle. Considerable research has been conducted on the rumen microbiota, but less consideration has been given to the rest of the alimentary tract.
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Harvey Freetly et al.Birth and weaning traits in crossbred cattle from Hereford, Angus, Norwegian Red, Swedish Red and White, Wagyu, and Friesian sireshttp://digitalcommons.unl.edu/hruskareports/378
http://digitalcommons.unl.edu/hruskareports/378Wed, 12 Oct 2016 12:13:05 PDT
The objective of this study was to characterize breeds representing diverse biological types for birth and weaning traits in crossbred cattle (Bos taurus). Gestation length, calving diffi culty, percentage of unassisted calving, percentage of perinatal survival, percentage of survival from birth to weaning, birth weight, weaning weight, BW at 205 d, and ADG was measured in 1,370 calves born and 1,285 calves weaned. Calves were obtained by mating Hereford, Angus, and MARC III (1/4 Hereford, 1/4 Angus, 1/4 Pinzgauer, and 1/4 Red Poll) mature cows to Hereford or Angus (British breeds), Norwegian Red, Swedish Red and White, Wagyu, and Friesian sires. Calves were born during the spring of 1997 and 1998. Sire breed was signifi cant for gestation length, birth weight, BW at 205 d, and ADG (P < 0.001). Offspring from Swedish Red and White and Friesian had the shortest gestation length (282 d), whereas offspring from Wagyu sires had the longest gestation length (286 d). Progeny from British breeds were the heaviest at birth (40.5 kg) and at 205 d (237 kg), and grew faster (0.97 kg/d) than offspring from other breeds. Offspring from Wagyu sires were the lightest at birth (36.3 kg) and at 205 d (214 kg), and had the slowest growth (0.91 kg/d). Dam breed was signifi cant for gestation length (P < 0.001), birth weight (P = 0.009), BW at 205 d, and ADG (P < 0.001). Offspring from Hereford cows had the longest gestation length (284 d), whereas offspring from Angus cows had the shortest (282 d). Offspring from MARC III cows were the heaviest at birth (39.4 kg) when compared with offspring from Hereford (38.2 kg) and Angus (38.6 kg) cows. Progeny from Angus cows were the heaviest at 205 d (235 kg) and grew faster (0.96 kg/d), whereas offspring from Hereford cows were the lightest at 205 d (219 kg) and were the slowest in growth (0.88 kg/d). Sex was signifi cant for gestation length (P = 0.026), birth weight, BW at 205 d, and ADG (P < 0.001). Male calves had a longer gestation length (284 d) when compared with female calves (283 d). Males were heavier than females at birth and at 205 d, and grew faster. Sire breed effects can be optimized by selection and use of appropriate crossbreeding systems.
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E. Casas et al.Growth curves of crossbred cows sired by Hereford, Angus,
Belgian Blue, Brahman, Boran, and Tuli bulls, and the fraction
of mature body weight and height at pubertyhttp://digitalcommons.unl.edu/hruskareports/377
http://digitalcommons.unl.edu/hruskareports/377Wed, 12 Oct 2016 12:10:49 PDT
The objective of this study was to evaluate the growth curves of females to determine if mature size and relative rates of maturation among breeds differed. Body weight and hip height data were fitted to the nonlinear function BW = f(age) = A − Bek×age, where A is an estimate of mature BW and k determines the rate that BW or height moves from B to A. Cows represented progeny from 28 Hereford, 38 Angus, 25 Belgian Blue, 34 Brahman, 8 Boran, and 9 Tuli sires. Bulls from these breeds were mated by AI to Angus, Hereford, and MARC III composite (1/4 Angus, ¼ Hereford, 1/4 Red Poll, and 1/4 Pinzgauer) cows to produce calves in 1992, 1993, and 1994. These matings resulted in 516 mature cows whose growth curves were subsequently evaluated. Hereford-sired cows tended to have heavier mature BW, as estimated by parameter A, than Angus- (P = 0.09) and Brahman-sired cows(P = 0.06), and were heavier than the other breeds (P < 0.001). Angus-sired cows were heavier than Boran-(P < 0.001) and Tuli-sired cows (P < 0.001), and tended to be heavier than Belgian Blue-sired cows (P = 0.097). Angus-sired cows did not differ from Brahman- sired cows (P = 0.94). Brahman-sired cows had a heavier mature BW than Boran- (P < 0.001), Tuli- (P < 0.001), and Belgian Blue-sired cows (P < 0.04). Angus-sired cows matured faster (k) than cows sired by Hereford (P = 0.03), Brahman (P < 0.001), Boran (P = 0.03), and Tuli (P < 0.001) sires, but did not differ from Belgian Blue-sired (P = 0.13) cows. Brahmansired cows took longer to mature than Boran- (P = 0.03) or Belgian Blue-sired cows (P = 0.003). Belgian Blue-sired cows were faster maturing than Tuli-sired cows (P = 0.02). Brahman-sired cows had reached a greater proportion of their mature BW at puberty than had Hereford- (P < 0.001), Tuli- (P = 0.003), and Belgian Blue-sired cows (P = 0.001). Boran-sired cows tended to have reached a greater proportion of their mature BW at puberty than had Angus-sired cows (P = 0.09), and had reached a greater proportion of their mature BW at puberty than had Hereford- (P < 0.001), Tuli- (P < 0.001), and Belgian Blue-sired cows (P < 0.001). Within species of cattle, the relative range in proportion of mature BW at puberty (Bos taurus 0.56 through 0.58, and Bos indicus 0.60) was highly conserved, suggesting that proportion of mature BW is a more robust predictor of age at puberty across breeds than is absolute weight or age.
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Harvey C. Freetly et al.Birth and weaning traits in crossbred cattle from Hereford, Angus, Brahman, Boran, Tuli, and Belgian Blue sireshttp://digitalcommons.unl.edu/hruskareports/376
http://digitalcommons.unl.edu/hruskareports/376Wed, 12 Oct 2016 12:05:11 PDT
The objective of this study was to characterize breeds representing diverse biological types for birth and weaning traits in crossbred cattle. Gestation length, calving difficulty, percentage of unassisted calving, percentage of perinatal survival, percentage of survival from birth to weaning, birth weight, BW at 200 d, and ADG were measured in 2,500 calves born and 2,395 calves weaned. Calves were obtained by mating Hereford, Angus, and MARC III (one-fourth Hereford, one-fourth Angus, one-fourth Pinzgauer, and one-fourth Red Poll) mature cows to Hereford or Angus (British breed), Brahman, Tuli, Boran, and Belgian Blue sires. Calves were born during the spring seasons of 1992, 1993, and 1994. Sire breed was significant for all traits (P < 0.002). Offspring from British breeds and the Belgian Blue breed had the shortest gestation length (285 d) when compared with progeny from other sire breeds (average of 291 d). Calving difficulty was greater in offspring from Brahman sires (1.24), whereas the offspring of Tuli sires had the least amount of calving difficulty (1.00). Offspring from all sire breeds had similar perinatal survival and survival from birth to weaning (average of 97.2 and 96.2%, respectively), with the exception of offspring from Brahman sires, which had less (92.8 and 90.4%, respectively). Progeny of Brahman sires were heaviest at birth (45.7 kg), followed by offspring from British breed, Boran, and Belgian Blue sires (average of 42.4 kg). The lightest offspring at birth were from Tuli sires (38.6 kg). Progeny derived from Brahman sires were the heaviest at 200 d (246 kg), and they grew faster (1.00 kg/d) than offspring from any other group. The progeny of British breeds and the Belgian Blue breed had an intermediate BW at 200 d (238 kg) and an intermediate ADG (average of 0.98 kg/d). The progeny of Boran and Tuli sires were the lightest at 200 d (227 kg) and had the least ADG (0.93 kg/d). Male calves had a longer gestation length, had a greater incidence of calving difficulty, had greater mortality to weaning, were heavier, and grew faster than female calves. Sire breed effects can be optimized by selection and use of appropriate crossbreeding systems.
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E. Casas et al.Prediction of genetic values for feed intake from individual body weight gain and total feed intake of the penhttp://digitalcommons.unl.edu/hruskareports/375
http://digitalcommons.unl.edu/hruskareports/375Wed, 12 Oct 2016 12:02:02 PDT
Records of individual feed intake (FI) and BW gain (GN) were obtained from the Germ Plasm Evaluation (GPE) program at US Meat Animal Research Center (USMARC). Animals were randomly assigned to pens. Only pens with 6 to 9 steers (n = 289) were used for this study (data set 1). Variance components and genetic parameters were estimated using data set 1. Estimated genetic values (EGV) for FI were calculated by 5 methods using single and 2-trait analyses: 1) individual FI and individual GN, 2) individual FI alone, 3) 2-trait with individual GN but with FI missing, 4) individual GN and pen total FI, and 5) pen total FI alone. Analyses were repeated but with some of the same records assigned artificially to 36 pens of 5 and 4 paternal half sibs per pen (data sets 2 and 3). Models included year as a fixed factor and birth and weaning weights, age on test, and days fed as covariates. Estimates of heritability were 0.42 ± 0.16 and 0.34 ± 0.17 for FI and GN. The estimate of the genetic correlation was 0.57 ± 0.23. Empirical responses to selection were calculated as the average EGV for the top and bottom 10% based on rank for each method but with EGV from method 1 substituted for the EGV on which ranking was based. With data set 1, rank correlations between EGV from method 1 and EGV from methods 2, 3, 4, and 5 were 0.99, 0.53, 0.32, and 0.15, respectively. Empirical responses relative to method 1 agreed with the rank correlations. Accuracy of EGV for method 4 (0.44) was greater than for method 3 (0.35) and for method 5 (0.29). Accuracies for methods 4 and 5 were greater than indicated by empirical responses and correlations with EGV from method 1. Comparisons of the 5 methods were similar for data sets 2 and 3. With data set 2, rank correlations between EGV from method 1 and EGV from methods 3, 4, and 5 were 0.47, 0.64, and 0.62. Average accuracies of 56, 75, and 75% relative to method 1 (0.67) generally agreed with the empirical responses to selection. As expected, accuracy using pen total FI and GN to obtain EGV for FI was greater than using GN alone. With data set 1, empirical response to selection with method 4 was one-third of that for method 1, although average accuracy was 65% of that for method 1. With assignment of 5 paternal half sibs to artificial pens, using pen total FI and individual GN was about 81% as effective for selection as using individual FI and GN to obtain EGV for FI and was substantially more effective than use of GN alone.
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A. J. Cooper et al.Postweaning growth and carcass traits in crossbred cattle
from Hereford, Angus, Brangus, Beefmaster, Bonsmara,
and Romosinuano maternal grandsireshttp://digitalcommons.unl.edu/hruskareports/374
http://digitalcommons.unl.edu/hruskareports/374Wed, 12 Oct 2016 11:57:40 PDT
The objective of this study was to characterize breeds representing diverse biological types for postweaning growth and carcass composition traits in terminal crossbred cattle. Postweaning growth and carcass traits were analyzed on 464 steers and 439 heifers obtained by mating F1 cows to Charolais and MARC III (1/4 Hereford, 1/4 Angus, 1/4 Pinzgauer, and ¼ Red Poll) sires. The F1 cows were obtained from mating Angus and MARC III dams to Hereford, Angus, Beefmaster, Brangus, Bonsmara, and Romosinuano sires. Traits evaluated were postweaning ADG, slaughter weight, HCW, dressing percentage, percentage of carcasses classified as USDA Choice, LM area, marbling score, USDA yield grade, fat thickness, retail product yield (percentage), and retail product weight. Maternal grandsire breed was significant (P < 0.05) for all traits. Animals with Angus grandsires grew faster and had the heaviest carcasses, with the greatest percentage of carcasses classified as USDA Choice and the greatest marbling scores when compared with other grandsire breeds. Animals with Romosinuano and Bonsmara inheritance grew slower, had the lightest weights at slaughter, the lightest carcass weights, the least percentage of carcasses classified as USDA Choice, and the least amount of marbling and fat thickness. Animals with inheritance from these 2 breeds had a more desirable yield grade with the greatest retail product yield. Maternal granddam breed was significant (P < 0.05) for marbling score, USDA yield grade, fat thickness, and retail product yield. Sex class was significant (P < 0.05) for all traits except for retail product yield. Steers grew faster, were heavier, had heavier carcasses, and were leaner than heifers. Heifers had a greater dressing percentage, a greater percentage of carcasses classified as USDA Choice, a greater LM area, and a decreased yield grade when compared with steers. Sire and grandsire breed effects can be optimized by selection and use of appropriate crossbreeding systems.
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E. Casas et al.Characterization of biological types of cattle (Cycle VIII): Carcass, yield, and longissimus palatability traitshttp://digitalcommons.unl.edu/hruskareports/373
http://digitalcommons.unl.edu/hruskareports/373Wed, 12 Oct 2016 11:51:59 PDT
The objective of this experiment was to evaluate alternative sources of tropically adapted cattle germplasm and compare them with Angus- (AN) and Hereford- (HE) sired steers. Carcass, yield, and longissimus thoracis palatability traits from F1 steers (n = 621) obtained from mating AN and MARC III cows to HE, AN, Brangus (BR), Beefmaster (BM), Bonsmara (BO), or Romosinuano (RO) sires were compared. Data were adjusted to constant age (426 d), carcass weight (340 kg), fat thickness (1.0 cm), fat trim percentage (25%), and marbling (Small00) endpoints. For Warner- Bratzler and slice shear force and trained and untrained sensory panel traits, data were obtained on LM from ribeye steaks stored at 2°C for 14 or 15 d postmortem. The following comparisons were from the age-constant endpoint. Carcasses from BM-, AN-, and BR-sired steers (358, 355, and 351 kg, respectively) were heavier (P < 0.05) than carcasses from steers from HE (343 kg) and BO (331 kg) sires; RO-sired steers (318 kg) had the lightest (P < 0.05) carcasses. Adjusted fat thicknesses for AN- and BM-sired steers (1.3 and 1.2 cm, respectively) were greater (P < 0.05) than for steers from BR (1.0 cm) and BO (0.9 cm) sires; RO-sired steers (0.8 cm) had the least fat thickness. Longissimus areas were larger (P < 0.05) for BO- and BR-sired steers (84.4 and 84.1 cm2, respectively) than for BM- and HE-sired steers (80.8 and 80.2 cm2, respectively). A greater (P < 0.05) percentage of carcasses from AN-sired steers graded USDA Choice (69%) than other sire breeds (17 to 47%) except HE (52%). Carcass yield of boneless, totally trimmed retail product was least (P < 0.05) for AN-sired steers (60.1%) and greatest (P < 0.05) for RO- and BO-sired steers (64.4 to 63.5%). Considering all measurements, AN LM tended to be more tender and BM LM tended to be least tender. American composite breeds BM and BR were heavier, fatter, lesser yielding, with similar marbling scores but less tender LM than BO and RO. Angus carcasses were similar in size, fatter, lesser yielding, with more marbling and more tender LM compared with BM and BR. Bonsmara and RO provide tropically adapted germplasm and produce carcasses that are lighter, leaner, greater yielding, with similar marbling and LM that tend to be more tender than carcasses from BM and BR.
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T. L. Wheeler et al.Using simulation models to predict feed intake: Phenotypic and genetic relationships between observed and predicted values in cattlehttp://digitalcommons.unl.edu/hruskareports/372
http://digitalcommons.unl.edu/hruskareports/372Tue, 11 Oct 2016 13:01:52 PDT
The objectives of this study were to evaluate the accuracy of the Decision Evaluator for the Cattle Industry (DECI) and the Cornell Value Discovery System (CVDS) in predicting individual DMI and to assess the feasibility of using predicted DMI data in genetic evaluations of cattle. Observed individual animal data on the average daily DMI (OFI), ADG, and carcass measurements were obtained from postweaning records of 504 steers from 52 sires (502 with complete data). The experimental data and daily temperature and wind speed data were used as inputs to predict average daily feed DMI (kg) required (feed required; FR) for maintenance, cold stress, and ADG; maintenance and cold stress; ADG; maintenance and ADG; and maintenance alone, with CVDS (CFRmcg, CFRmc, CFRg, CFRmg, and CFRm, respectively) and DECI (DFRmcg, DFRmc, DFRg, DFRmg, and DFRm, respectively). Genetic parameters were estimated by REML using an animal model with age on test as a covariate and with genotype, age of dam, and year as fixed effects. Regression equations for observed on predicted DMI were OFI = 1.27 (SE = 0.27) + 0.83 (SE = 0.04) × CFRmcg [R2 = 0.44, residual SD (sy.x) = 0.669 kg/d] and OFI = 1.32 (SE = 0.22) + 0.8 (SE = 0.03) × DFRmcg (R2 = 0.53, sy.x = 0.612 kg/d). Heritability of OFI was 0.27 ± 0.12, and heritabilities ranged from 0.33 ± 0.12 to 0.41 ± 0.13 for predicted measures of DMI. Phenotypic and genetic correlations between OFI and CFRmcg, CFRmc, CFRg, CFRmg, CFRm, DFRmcg, DFRmc, DFRg, DFRmg, and DFRm were 0.67, 0.73, 0.41, 0.63, 0.78, 0.73, 0.82, 0.45, 0.77, and 0.86 (P < 0.001 for all phenotypic correlations); and 0.95 ± 0.07, 0.82 ± 0.13, 0.89 ± 0.09, 0.95 ± 0.07, 0.91 ± 0.09, 0.96 ± 0.07, 0.89 ± 0.09, 0.88 ± 0.09, 0.96 ± 0.06, and 0.96 ± 0.07, respectively. Phenotypic and genetic correlations between CFRmcg and DFRmcg, CFRmc and DFRmc, CFRg and DFRg, CFRmg and DFRmg, and CFRm and DFRm were 0.98, 0.94, 0.99, 0.98, and 0.95 (P < 0.001 for all phenotypic correlations), and 0.99 ± 0.004, 0.98 ± 0.017, 0.99 ± 0.004, 0.99 ± 0.005, and 0.97 ± 0.021, respectively. The strong genetic relationships between OFI and CFRmcg, CFRmg, DFRmcg, and DFRmg indicate that these predicted measures of DMI may be used in genetic evaluations and that DM requirements for cold stress may not be needed, thus reducing model complexity. However, high genetic correlations for final weight with OFI, CFRmcg, and DFRmcg suggest that the technology needs to be further evaluated in populations with genetic variance in feed efficiency.
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C. B. Williams et al.Postweaning growth and carcass traits in crossbred cattle from Hereford, Angus, Norwegian Red, Swedish Red and White, Friesian, and Wagyu maternal grandsireshttp://digitalcommons.unl.edu/hruskareports/371
http://digitalcommons.unl.edu/hruskareports/371Tue, 11 Oct 2016 12:49:16 PDT
The objective of this study was to characterize breeds representing diverse biological types for postweaning growth and carcass composition traits in terminal crossbred cattle. Postweaning growth and carcass traits were analyzed on 434 steers and 373 heifers obtained by mating F1 cows to Charolais sires. Maternal grandsires represented Hereford, Angus, and MARC III (1/4 Hereford, 1⁄4 Angus, 1⁄4 Pinzgauer, and 1⁄4 Red Poll) dams to Hereford or Angus (British Breeds), Norwegian Red, Swedish Red and White, Wagyu, or Friesian breeds. Breed groups were slaughtered serially in each of 2 yr (2002 and 2003). Postweaning ADG, slaughter weight, hot carcass weight, dressing percentage, percentage Choice, LM area, marbling score, USDA yield grade, fat thickness, retail product yield (percentage), retail product weight, fat yield (percentage), fat weight, bone yield (percentage), and bone weight were analyzed. Maternal grandsire breed was significant (P < 0.05) for all traits except dressing percentage, percentage Choice, and LM area. Marbling score for animals with Norwegian Red, Wagyu, Swedish Red and White, British Breeds, and Friesian inheritance was 550, 544, 532, 530, and 515, respectively (SEM = 8). Retail product weight for these animals was 224, 211, 227, 223, and 223 kg, respectively (SEM = 2 kg). Maternal granddam breed was not significant for any of the traits analyzed. Grandsire breed effects can be optimized by selection and use of appropriate crossbreeding systems.
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E. Casas et al.Characterization of biological types of cattle (Cycle VII):
Carcass, yield, and longissimus palatability traitshttp://digitalcommons.unl.edu/hruskareports/370
http://digitalcommons.unl.edu/hruskareports/370Tue, 11 Oct 2016 12:41:06 PDT
The objective of this experiment was to provide a current evaluation of the seven most prominent beef breeds in the United States and to determine the relative changes that have occurred in these breeds since they were evaluated with samples of sires born 25 to 30 yr earlier. Carcass (n = 649), yield (n = 569), and longissimus thoracis palatability (n = 569) traits from F1 steers obtained from mating Hereford, Angus, and MARC III cows to Hereford (H), Angus (A), Red Angus (RA), Charolais (C), Limousin (L), Simmental (S), or Gelbvieh (G) sires were compared. Data were adjusted to constant age (445 d), carcass weight (363 kg), fat thickness (1.1 cm), fat trim percent (25%), and marbling (Small35) endpoints. For Warner-Bratzler shear force and trained sensory panel traits, data were obtained on LM from steaks stored at 2°C for 14 d postmortem. The following comparisons were from the age-constant endpoint. Carcasses from L-, G-, and Hsired steers (361, 363, and 364 kg, respectively) were lighter (P < 0.05) than carcasses from steers from all other sire breeds. Adjusted fat thickness for carcasses from A-, RA-, and H-sired steers (1.5, 1.4, and 1.3 cm, respectively) was higher (P < 0.05) than for carcasses from steers from all other sire breeds (0.9 cm). Longissimus muscle areas were largest (P < 0.05) for carcasses from L-, C-, S-, and G-sired steers (89.9, 88.7, 87.6, and 86.5 cm2, respectively) and smallest for carcasses from H- and RA-sired steers (79.5 and 78.4 cm2). A greater (P < 0.05) percentage of carcasses from RA- and A-sired steers graded USDA Choice (90 and 88%, respectively) than from carcasses from other sire breeds (57 to 66%). Carcass yield of boneless, totally trimmed retail product was least (P < 0.05) for RA- and A-sired steers (59.1 and 59.2%, respectively) and greatest (P < 0.05) for G-, L-, C-, and S-sired steers (63.0 to 63.8%). Longissimus muscle from carcasses of A-sired steers (4.0 kg) had lower (P < 0.05) Warner Bratzler shear force values than LM from carcasses of G- and C-sired steers (4.5 to 4.3 kg, respectively). Trained sensory panel tenderness and beef flavor intensity ratings for LM did not differ (P < 0.05) among the sire breeds. Continental European breeds (C, L, S, and G) were still leaner, more heavily muscled, and had higher-yielding carcasses than did British breeds (H, A, and RA), with less marbling than A or RA, although British breeds have caught up in growth rate.
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T. L. Wheeler et al.Characterization of biological types of cattle (Cycle VI): Carcass, yield, and longissimus palatability traitshttp://digitalcommons.unl.edu/hruskareports/369
http://digitalcommons.unl.edu/hruskareports/369Tue, 11 Oct 2016 12:33:50 PDT
Carcass (n = 568) and longissimus thoracis palatability (n = 460) traits from F1 steers obtained from mating Hereford (H), Angus (A), and U.S. Meat Animal Research Center (MARC) III cows to H, A, Norwegian Red (NR), Swedish Red and White (RW), Friesian (F), or Wagyu (W) sires were compared. Data were adjusted to constant age (471 d), carcass weight (356 kg), fat thickness (1.0 cm), percentage of fat trim (24%), and marbling (Small35) end points. For Warner-Bratzler shear force and trained sensory panel traits, data were obtained on longissimus thoracis steaks stored at 2°C for 14 d postmortem. The following comparisons were from the age-constant end point. Carcasses from H- and A-sired steers (377 and 374 kg, respectively) were the heaviest (P < 0.05) and carcasses from W-sired steers (334 kg) were the lightest (P < 0.05). A greater (P < 0.05) percentage of carcasses from Aand W-sired steers graded USDA Choice (88 and 85%, respectively) than carcasses from other sire breeds (52 to 71%). Adjusted fat thickness for carcasses from Asired steers (1.3 cm) was highest (P < 0.05), followed by H-sired steers (1.1 cm) and W- and F-sired steers (0.9 cm); NR- and RW-sired steers (0.8 cm) had the lowest (P < 0.05) adjusted fat thickness. Longissimus thoracis area was not different (P > 0.05) among sire breeds (mean = 80.6 cm2). Carcass yield of boneless, totally trimmed retail product was least (P < 0.05) for A-sired steers (60.1%), intermediate for H-sired steers (61.5%), and similar (P > 0.05) for all other sire breeds (62.5 to 62.8%). Longissimus thoracis steaks from carcasses of A- (3.7 kg) and W-sired (3.7 kg) steers had lower (P < 0.05) shear force values than longissimus thoracis steaks from other sire breeds (4.1 to 4.2 kg). Trained sensory panel tenderness, juiciness, or beef flavor intensity ratings for longissimus thoracis steaks did not differ (P > 0.05) among the sire breeds. Sire breed comparisons were affected by adjusting data to other end points. Heritability estimates for various carcass, yield, and palatability traits ranged from very low (h2 = 0.06 for percentage of kidney, pelvic, and heart fat) to relatively high (h2 = 0.71 for percentage of retail product yield). Relative to the other sire breeds, Wsired steers had the highest percentage of USDA Choice, Yield grade 1 and 2 carcasses, but their carcasses were the lightest.
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T. L. Wheeler et al.Association of myostatin on early calf mortality, growth, and carcass composition traits in crossbred cattlehttp://digitalcommons.unl.edu/hruskareports/368
http://digitalcommons.unl.edu/hruskareports/368Tue, 11 Oct 2016 12:18:09 PDT
The objective of this study was to investigate a potential association of an inactive myostatin allele with early calf mortality, and evaluate its effect on growth and carcass traits in a crossbred population. Animals were obtained by mating F1 cows to F1 (Belgian Blue x British Breed) or Charolais sires. Cows were obtained from mating Hereford, Angus, and MARC III ( ¼ Hereford, ¼ Angus, ¼ Pinzgauer, and ¼ Red Poll) dams to Hereford, Angus, Tuli, Boran, Brahman, or Belgian Blue sires. Belgian Blue was the source of the inactive myostatin allele. Myostatin genotypes were determined for all animals including those that died before weaning. Early calf mortality was examined in the F2 subpopulation (n = 154), derived from the F1 siresmated to F1 cows from Belgian Blue sires, to evaluate animals with zero, one, or two copies of inactive myostatin allele. An overall 1:2:1 ratio (homozygous active myostatin allele:heterozygous:homozygous inactive myostatin allele) was observed in the population; however, a comparison between calves dying before weaning and those alive at slaughter showed an unequal distribution across genotypes (P < 0.01). Calves with two copies of the inactive allele were more likely (P < 0.01) to die before weaning. Postweaning growth traits were evaluated in the surviving animals (n = 1,370), including birth, weaning, and live weight at slaughter, and postweaning ADG. Carcass composition traits analyzed were hot carcass weight, fat thickness, LM area, marbling score, USDA yield grade, estimated kidney, pelvic, and heart fat, retail product yield and weight, fat yield and weight, bone yield and weight, and percentage of carcasses classified as Choice. Charolais lack the inactive myostatin allele segregating in Belgian Blue; thus, in the population sired by Charolais (n = 645), only animals with zero or one copy of the inactive myostatin allele were evaluated. Animals carrying one copy were heavier at birth and at weaning, and their carcasses were leaner and more muscled. In the population sired by Belgian Blue × British Breed (n = 725), animals with two copies of inactive myostatin allele were heavier at birth, leaner, and had a higher proportion of muscle mass than animals with zero or one copies. Heterozygous animals were heaviest at weaning and had the highest live weight, whereas animals with zero copies had the highest fat content. The use of the inactive myostatin allele is an option to increase retail product yield, but considerations of conditions at calving are important to prevent mortality.
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E. Casas et al.The relationship between ultrasound measurements and carcass fat thickness and longissimus muscle area in beef cattlehttp://digitalcommons.unl.edu/hruskareports/367
http://digitalcommons.unl.edu/hruskareports/367Tue, 11 Oct 2016 12:10:08 PDT
Five hundred thirty-four steers were evaluated over a 2-yr period to determine the accuracy of ultrasonic estimates of carcass 12th-rib fat thickness (CFAT) and longissimus muscle area (CLMA). Within 5 d before slaughter, steers were ultrasonically measured for 12th-rib fat thickness (UFAT) and longissimus muscle area (ULMA) using an Aloka 500V real-time ultrasound machine equipped with a 17.2-cm, 3.5-MHz linear transducer. Overall, correlation coefficients between ultrasound and carcass fat and longissimus muscle area were 0.89 and 0.86, respectively. Correlations for UFAT with CFAT were similar between years (0.86 and 0.90), whereas the relationship between ULMA and CLMA was stronger in yr 1 (r = 0.91; n = 282) than in yr 2 (r = 0.79; n = 252). Differences between ultrasonic and carcass measurements were expressed on both an actual (FDIFF and RDIFF) and absolute (FDEV and RDEV) basis. Mean FDIFF and RDIFF indicated that ultrasound underestimated CFAT by 0.06 cm and overestimated CLMA by 0.71 cm2 across both years. Overall mean FDEV and RDEV, which are indications of the average error rate, were 0.16 cm and 3.39 cm2, respectively. Analysis of year effects revealed that FDIFF, FDEV, and RDEV were greater (P < 0.01) in magnitude in yr 1. Further analysis of FDEV indicated that leaner (CFAT < 0.51 cm) cattle were overestimated and that fatter (CFAT > 1.02 cm) cattle were underestimated with ultrasound. Similarly, steers with small CLMA (<71.0 cm2) were overestimated, and steers with large CLMA (>90.3 cm2) were underestimated. The thickness of CFAT had an effect (P < 0.05) on the error of UFAT and ULMA measurements, with leaner animals being more accurately evaluated for both traits. Standard errors of prediction (SEP) adjusted for bias of ultrasound measurements were 0.20 cm and 4.49 cm2 for UFAT and ULMA, respectively. Differences in SEP were observed for ULMA, but not UFAT, by year. These results indicate that ultrasound can be an accurate estimator of carcass traits in live cattle when measurements are taken by an experienced, well-trained technician, with only small differences in accuracy between years.
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S. P. Greiner et al.Prediction of retail product weight and percentage using ultrasound and carcass measurements in beef cattlehttp://digitalcommons.unl.edu/hruskareports/366
http://digitalcommons.unl.edu/hruskareports/366Tue, 11 Oct 2016 12:03:04 PDT
Data from 534 steers representing six sire breed groups were used to develop live animal ultrasound prediction equations for weight and percentage of retail product. Steers were ultrasonically measured for 12th-rib fat thickness (UFAT), rump fat thickness (URPFAT), longissimus muscle area (ULMA), and body wall thickness (UBDWALL) within 5 d before slaughter. Carcass measurements included in USDA yield grade (YG) and quality grade calculations were obtained. Carcasses were fabricated into boneless, totally trimmed retail products. Regression equations to predict weight and percentage of retail product were developed using either live animal or carcass traits as independent variables. Most of the variation in weight of retail product was accounted for by live weight (FWT) and carcass weight with R2 values of 0.66 and 0.69, respectively. Fat measurements accounted for the largest portion of the variation in percentage of retail product when used as single predictors (R2 = 0.54, 0.44, 0.23, and 0.54 for UFAT, URPFAT, UBDWALL, and carcass fat, respectively). Final models (P < 0.10) using live animal variables included FWT, UFAT, ULMA, and URPFAT for retail product weight (R2 = 0.84) and UFAT, URPFAT, ULMA, UBDWALL, and FWT for retail product percentage (R2 = 0.61). Comparatively, equations using YG variables resulted in R2 values of 0.86 and 0.65 for weight and percentage of retail product, respectively. Results indicate that live animal equations using ultrasound measurements are similar in accuracy to carcass measurements for predicting beef carcass composition, and alternative ultrasound measurements of rump fat and body wall thickness enhance the predictive capability of live animal-based equations for retail yield.
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S. P. Greiner et al.Maternal grandsire, granddam, and sire breed effects on growth and carcass traits of crossbred cattlehttp://digitalcommons.unl.edu/hruskareports/365
http://digitalcommons.unl.edu/hruskareports/365Tue, 11 Oct 2016 11:57:06 PDT
Postweaning growth, feed efficiency, and carcass traits were analyzed on 1,422 animals obtained by mating F1 cows to F1 (Belgian Blue X British breeds) or Charolais sires. Cows were obtained from mating Hereford, Angus, and MARC III ( ¼ Hereford, ¼ Angus, ¼ Pinzgauer, and ¼ Red Poll) dams to Hereford or Angus (British breeds), Tuli, Boran, Brahman, or Belgian Blue sires. Breed groups were fed in replicated pens and slaughtered serially in each of 2 yr. Postweaning average daily gain; live weight; hot carcass weight; fat depth; longissimus area; estimated kidney, pelvic, and heart fat (percentage); percentage Choice; marbling score; USDA yield grade; retail product yield (percentage); retail product weight; fat yield (percentage); fat weight; bone yield (percentage); and bone weight were analyzed in this population. Quadratic regressions of pen mean weight on days fed and of cumulative ME consumption on days fed were used to estimate gain, ME consumption and efficiency (Mcal of ME/kg of gain) over time (0 to 200 d on feed), and weight (300 to 550 kg) intervals. Maternal grandsire breed was significant (P < 0.01) for all traits. Maternal granddam breed (Hereford, Angus, or MARC III) was significant (P < 0.05) only for fat depth, USDA yield grade, retail product yield, fat yield, fat weight, and bone yield. Sire breed was significant (P < 0.05) for live weight, hot carcass weight, longissimus area, and bone weight. Sex class was a significant (P < 0.001) source of variation for all traits except for percentage Choice, marbling score, retail product yield, and fat yield. Interactions between maternal grandsire and sire breed were nonexistent. Sire and grandsire breed effects can be optimized by selection and use of appropriate crossbreeding systems.
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E. Casas et al.Growth and pubertal development in Brahman-, Boran-, Tuli-,
Belgian Blue-, Hereford- and Angus-sired F1 bullshttp://digitalcommons.unl.edu/hruskareports/364
http://digitalcommons.unl.edu/hruskareports/364Tue, 11 Oct 2016 11:48:58 PDT
Growth and testicular development between 7 and 15 mo of age were evaluated in bulls produced by mating sires of six breeds (Hereford, Angus, Belgian Blue, Brahman, Boran, and Tuli) to Angus, Hereford, and MARC III (four-breed composite) cows. At 12 mo of age, Angus- and Hereford-sired bulls had the heaviest body weight (P < 0.08 to 0.001), whereas Brahman- and Belgian Blue-sired bulls were intermediate, and Boran- and Tuli-sired bulls weighed the least. Bulls sired by European breeds grew more rapidly after weaning (P < 0.01) than did Brahman-, Boran-, and Tuli-sired bulls, and these differences in growth rate were maintained through 15 mo of age, indicating that offspring of heat-adapted sire breeds (Brahman, Boran, and Tuli) have lower postweaning rates of gain, particularly during winter months, than do offspring of nonheat adapted sire breeds. Testis size was smaller initially (P < 0.01) and remained smaller in offspring of heat-adapted sire breeds through yearling age. By 15 mo of age, testis size was largest (P < 0.06 to 0.001) in Angus-sired bulls and had become similar among Hereford-, Brahman-, Boran- and Belgian Blue-sired bulls but remained smaller (P < 0.02 to 0.001) in Tulisired bulls. Thus, offspring of heat-adapted sire breeds had delayed testicular development compared with that of nonheat adapted sire breeds, particularly through yearling age. At puberty, Angus-sired bulls were 23 to 82 d younger (P < 0.05 to 0.001) than all other sire breeds except Hereford, and Brahman-sired bulls were older at puberty (P < 0.05 to 0.001) than were bulls of all other sire breeds except Boran. Testis size at puberty was quite similar among breeds of bulls (scrotal circumference = 27.9 ± 0.1 cm) despite large breed differences in age, body weight, and hip height. Thus, measurement of yearling testis size was a reliable indicator of age at puberty among widely divergent breeds of bulls. In addition, the lower postweaning rates of gain and the smaller and slower testicular development in offspring of heat-adapted sire breeds should be noted by cattle producers considering use of such breeds in crossbreeding and breed improvement programs.
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D. D. Lunstra et al.Accuracy of predicting weight and percentage of beef carcass retail product using ultrasound and live animal measureshttp://digitalcommons.unl.edu/hruskareports/363
http://digitalcommons.unl.edu/hruskareports/363Tue, 11 Oct 2016 11:42:45 PDT
Five hundred thirty-four steers were evaluated over a 2-yr period to develop and validate prediction equations for estimating carcass composition from live animal ultrasound measurements and to compare these equations with those developed from carcass measurements. Within 5 d before slaughter, steers were ultrasonically measured for 12th-rib fat thickness (UFAT), longissimus area (ULMA), rump fat thickness (URPFAT), and body wall thickness (UBDWALL). Carcasses were fabricated to determine weight (KGRPRD) and percentage (PRPRD) of boneless, totally trimmed retail product. Data from steers born in Year 1 (n = 282) were used to develop prediction equations using stepwise regression. Final models using live animal variables included live weight (FWT), UFAT, ULMA, and URPFAT for KGRPRD (R2 = 0.83) and UFAT, URPFAT, ULMA, FWT, and UBDWALL for PRPRD (R2 = 0.67). Equations developed from USDA yield grade variables resulted in R2 values of 0.87 and 0.68 for KGRPRD and PRPRD, respectively. When these equations were applied to steers born in Year 2 (n = 252), correlations between values predicted from live animal models and actual carcass values were 0.92 for KGRPRD, and ranged from 0.73 to 0.76 for PRPRD. Similar correlations were found for equations developed from carcass measures (r = 0.94 for KGRPRD and 0.81 for PRPRD). Both live animal and carcass equations overestimated (P < 0.01) actual KGRPRD and PRPRD. Regression of actual values on predicted values revealed a similar fit for equations developed from live animal and carcass measures. Results indicate that composition prediction equations developed from live animal and ultrasound measurements can be useful to estimate carcass composition.
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S. P. Greiner et al.